It comes as fire brigades across the region face cuts which firefighters say could endanger them or the public.

They include fire engines being replaced with 4x4s at some stations in Norfolk, a move which is currently under review, while appliances in Suffolk are being crewed by three instead of five firefighters.

Cameron Matthews, regional chair of the Fire Brigades Union, said the money could have paid for 20 on-call fire stations or 65 whole-time firefighters.

"In our region Suffolk are suffering the worst," he said. "They're going out with crews of three because they're failing to recruit and retain on-call firefighters. Part of that is down to pay and conditions."

Firefighters' pay has fallen by more than £6,000 in real terms over the last decade Picture: Chris Bishop

He added whole-time firefighters were being made to train on their days off, while pay had fallen by more than £6,000 in real terms over the last decade.

The MHCLG said it was in negotiations with a potential tenant over the Cambridgeshire site.

A 25-year lease agreed when the building was commissioned means the government can not sell it but it can be sub-leased to another party.